[quote=@Ace of flames01]
[@Dark Light] I could make a NPC to be an antagonist (my idea from before) 
[/quote]

Yea go for it if no one bites but I like the unpredictability of another player character. Originally a lot of the subterfuge will be in the interaction, how are they going to befriend you and find out what's going on? Will they feel sorry for you when they find out that they might get you killed. How will you react when you learn of their deception!? 

It's not quite the same if you play both sides.
But the long term antagonist will be setting up some short term enemies to overcome. They will most defiantly be NPC's. Assassins sent off the antagonists information. Antagonist might even have to seperate is or lure you somewhere. It will all be in the emails.

Edit: Now hurry up and reply!